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Snake, active contour or deformable active contour has been widely used in medical image segmentation area. In this paper, comparison between Gradient Vector Flow (GVF) snake and Enhanced Distance (ED) snake in segmenting microcalcifications is carried out. The performance is measured based on actual area of the average percentage difference traced by expert radiologists. Results obtained shows that the values of average percentage difference for the GVF and ED snake are 4.3% and 6.68% respectively. These results indicate that the GVF snake has better performance with 95.7%.

Spray coating technology is an advanced manufacturing process to break the liquid down into small droplets and disperse these droplets uniformly on the target substrate. The nozzle used in this fabrication process rapidly disintegrates the liquid jet at a direction of motion governed mainly by the prevailing airflow pattern in the spray region environment. According to Navier–Stokes energy equation, the fluid and environmental temperature capable of supplying additional energy to the droplet imparted the ejected liquid jet from the nozzles. With a view to understanding the liquid droplet behaviour at elevated temperatures, this study investigates the jet velocity, pressure, and temperature of ethanol at its evaporation temperature of 360 K using commercial CFD software (ANSYS FLUENT 2020). A numerical simulation of a simple nozzle system with a cone angle of 56° and an outlet radius of 0.1966 mm was modelled at 1 bar inlet pressure to study the effect of the environment temperature on the liquid jet. The result from the temperature profile showed that the liquid jet exhibited turbulence or a swirling effect at elevated temperature as the liquid absorbed thermal energy. The liquid jet temperature increased to the maximum temperature of +3K at a liquid jet distance of 10 cm when compared with normal environment temperature. This numerical study showed that environmental conditions such as temperature can impact the liquid jet quality and properties, which are difficult to observe during experimental work. It is expected that the finding from this work would benefit the industries, leading to better spray nozzle design for future coating applications.

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Stochastic spatial models are becoming a popular tool for understand the ecological and evolution of ecosystem problems. We consider the predator prey interactions in term of stochastic representation of this Lotka-Volterra model and explore the use of stochastic processes to extinction behavior of the interacting populations. Here, we present simulation of stochastic processes of continuous time Lotka-Volterra model. Euler method has been used to solve the predator prey system. The trajectory spiral graph has been plotted based on obtained solution to show the population cycle of predator as a function of time.